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Registro Completo |
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Biblioteca(s): |
Embrapa Meio Norte / UEP-Parnaíba. |
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Data corrente: |
22/06/1998 |
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Data da última atualização: |
17/02/2009 |
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Autoria: |
KELLEY, K. R.; STEVENSON, F. J. |
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Título: |
Forms and nature of organic N in soil. |
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Ano de publicação: |
1995 |
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Fonte/Imprenta: |
Fertilizer Research, v. 42, p. 1-11, 1995. |
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Idioma: |
Inglês |
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Conteúdo: |
Most of the N in surface soils occurs in organic forms. The organic N in soil plays a key role in plant nutrition and soil fertility through its effects on microbial activity and nutrient availability. Typically, about one-third of the fertilizer N applied to temperate-zone soils is immobilized and retained in organic forms at the end of the growing season. A significant portion of this newly immobilized N is no more available to microorganims and plants than the native humus N. Stabilization processes, probably involving polymerization of amino compounds and polyphenols, result in incorporation of N into humic substances with a concurrent reduction in N availability. This paper presents an account of the forms and nature of organic N in soil, emphasizing possible formation pathways, chemical characterization of humic substances through conventional and solid-state techniques, and the fate and composition of newly immobilized N in soil. |
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Palavras-Chave: |
Substância húmica. |
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Thesagro: |
Nitrogênio. |
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Categoria do assunto: |
-- |
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Marc: |
LEADER 01352naa a2200157 a 4500
001 1079312
005 2009-02-17
008 1995 bl --- 0-- u #d
100 1 $aKELLEY, K. R.
245 $aForms and nature of organic N in soil.
260 $c1995
520 $aMost of the N in surface soils occurs in organic forms. The organic N in soil plays a key role in plant nutrition and soil fertility through its effects on microbial activity and nutrient availability. Typically, about one-third of the fertilizer N applied to temperate-zone soils is immobilized and retained in organic forms at the end of the growing season. A significant portion of this newly immobilized N is no more available to microorganims and plants than the native humus N. Stabilization processes, probably involving polymerization of amino compounds and polyphenols, result in incorporation of N into humic substances with a concurrent reduction in N availability. This paper presents an account of the forms and nature of organic N in soil, emphasizing possible formation pathways, chemical characterization of humic substances through conventional and solid-state techniques, and the fate and composition of newly immobilized N in soil.
650 $aNitrogênio
653 $aSubstância húmica
700 1 $aSTEVENSON, F. J.
773 $tFertilizer Research$gv. 42, p. 1-11, 1995.
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Registro original: |
Embrapa Meio Norte / UEP-Parnaíba (CPAMN-UEPP) |
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